THERMODYNAMICS

Dr. R. Suya Padhra Haridha

Assistant Professor of Physics

A.P.C. Mahalaxmi College for Women

Thoothukudi

What is thermodynamics?

• The study of thermodynamics is concerned with ways energy is stored within a body and how energy transformations, which involve heat and work, may take place

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• Approaches to studying thermodynamics
• Macroscopic (Classical thermodynamics)
• study large number of particles (molecules) that make up the substance in question
• does not require knowledge of the behavior of individual molecules
• Microscopic (Statistical thermodynamics)
• concerned within behavior of individual particles (molecules)
• study average behavior of large groups of individual particles

Thermodynamic Systems

• Thermodynamic System
• quantity of matter or a region of space chosen for study
• Boundary
• real or imaginary layer that separates the system from its surroundings
• Surroundings
• physical space outside the system boundary
• Types of Systems
• Closed
• Open

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Closed Systems (fixed masses)

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Energy, not mass, crosses closed-system boundaries

Open Systems (Control Volumes)

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Mass and Energy Cross Control Volume Boundaries

Isolated System

• Closed system where no heat or work (energy) may cross the system boundary
• Typically a collection of the main system (or several systems) and its surroundings is considered an isolated system

Applications of Thermodynamics

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